Devices connected in wireless networks can create a lot of data related to the mobility of the devices. This data can be used in many application areas. It is understood that the more connected “things” become, the more data related to mobility of a device becomes available. In particular, by collecting location data from all wirelessly connected devices it is possible to construct models of how these devices are moved around. Wireless networks that implement mechanisms to establish a connection with their wireless devices may keep track of device locations for paging and/or management of network resources.
Location information about the mobility of devices may be generated, for example:                in the device when it performs measurements on the signal strengths towards nearby radio base stations or access points in order to know which radio base station/access point to use for wireless communications;        in the wireless network when the device reports its location or connects to a radio base station/access point in the network. Devices may typically report their location whenever they move between larger predefined service areas, when they are in an active state, receive or send communications, and/or on a periodic basis.        
While this location information is primarily collected and maintained to facilitate the paging of the devices, it can also be used to build statistics and reports on the devices' locations by matching the service areas with a geo-spatial location.
Wireless communication networks may comprise or represent any wireless network used for wireless communications with devices connected to the wireless network. Examples of wireless networks include, but are not limited to, wireless networks such as the Worldwide Interoperability for Microwave Access (WiMAX), wireless local area networks (WLAN) based on the Institute of Electrical and Electronics Engineers' (IEEE) 802.11 standards e.g. Wi-Fi networks, or wireless networks based on cellular or satellite technologies such as femtocell networks, Global System for Mobile Communications (GSM), Wideband Code Division Multiple Access (W-CDMA), CDMA2000 or Long Term Evolution (LTE)/LTE Advanced mobile networks or any 2nd, 3rd or 4th Generation and beyond wireless networks.
The device(s) or connected device(s) as described herein may comprise or represent any device that is capable of connecting to or communicating over a wireless communication network. Non-stationary devices may comprise or represent any device that is mobile or moveable and connects to or communicates over a wireless network. Stationary devices may comprise or represent any device that is considered fixed or not typically moved and connects to or communicates over a wireless network. Examples of non-stationary devices include, but are not limited to, wireless devices such as mobile phones, terminals, smart phones, satellite phones, portable computing devices such as lap tops, handheld devices, tablets, netbooks, computers, personal digital assistants, and in-vehicle devices such as vehicle tracking systems or any other wireless communication device that is mobile. Examples of stationary devices include, but are not limited to, wireless devices such as sensors, smart meters or utility meters.
FIG. 1a is a schematic illustration of a wireless network 100 that includes a plurality of service areas (SAs) 102a-102d serving a plurality of devices 104a-104f. Each of the SAs 102a-102d may comprise or represent an area or region that is serviced by a wireless transceiver that allows the devices 104a-104f to connect to or communicate with or over the wireless network 100. Examples of SAs include, but are not limited to, SAs such as cells in cellular mobile networks that are served by base stations, wireless hotspots in a wireless LAN or WiFi network that are served access points, or satellite coverage areas or footprints serviced by satellites, or any area that is served by a transmitter/transceiver for connecting a device to a wireless network.
The SAs 102a-102d have service area identifiers (SA-ids) SA1-SA4, and the plurality of devices 104a-104f include a plurality of non-stationary devices 104d-104e and a plurality of stationary devices 104a-104c. It can be seen that SA 102a (SA-id: SA1) provides wireless network coverage for non-stationary device 104d, and SA 102b (SA-id: SA2) provides wireless network coverage for non-stationary devices 104e and 104d. 
The wireless network 100 described in FIG. 1a may maintain information on the location of the non-stationary devices. This information may be gathered from location updates or SA updates from the plurality of devices 104a-104e. SA updates may comprise or represent any location information associated with a device and the service area that is serving the device. Examples of SA updates may include, but are not limited to, an SA update such as data representative of location information such as a SA identifier identifying the SA, a device identifier, and/or a time stamp (this may be added by the network or device). The device identifier may be any identifier that can be used to identify the SA updates associated with that device.
The SA updates may be gathered and stored by the wireless network 100 from the plurality of devices 104a-104e, as shown in Table 1 below:
TABLE 1Latest SA update records maintained by the networkSA identifierDevice identifierTimeSA 1NSD12012 07 06 14:23:37SA 2NSD22012 07 06 14:23:42SA 2NSD32012 07 06 14:23:51
Each row of the table represents the information gathered from SA or location updates that include the SA identifier (or SA-id), the device identifier, and a time stamp of the latest SA update recorded by the wireless network 100. The device identifier may comprise or represent any identifier that may be used to uniquely identify the SA updates in relation to that device.
By using information about the SA that a device has been in at a specific time, it is possible to describe the mobility of that device. This can be done by a system integrated with a wireless network 100 that can collect all events generated from the devices. In a system integrated with the wireless network 100, it is also possible to directly use information about the layout of the wireless network 100 to calculate an estimated location of the device based on the SA-ids reported.
With the increasing popularity of devices that connect to wireless networks such as advanced smart phones and other advanced mobile devices it is now possible to create systems that track the mobility of its users without being integrated with the wireless network 100. In such a system an application (e.g. an Android® application) could collect the information of nearby SAs from the device. This information may be sent over the Internet to a server that uses a publicly available database (e.g. location-api.com or Google Location API) of the location of the wireless network transceivers (e.g. access points or radio base stations) to estimate the location of the device. A system implemented in this way could be called an over-the-top (OTT) location solution. The information of nearby SAs from the device may be used to notify the user of nearby goods and services (e.g. shops and restaurants) that may be of interest to the user.
In reality, the coverage areas of each SA are never mutually exclusive; SAs can overlap to maintain optimum coverage for the devices. As a result, for a given physical location, a device can be attached to one or more distinct SAs. Moreover, for a given physical location, the SA to which a device is attached (or connected) can change in time.
FIG. 1b is a schematic illustration of the wireless network 100 in which some of the plurality of SAs 102a-102d now overlap such that multiple SAs serve the same non-stationary device 104d. This is an example of device 104d having coverage of two overlapping SAs 102c and 102d. This may occur because the coverage area of any of the SAs 102a-102d can change during the management of the wireless network 100, e.g. the wireless network 100 may control the coverage of each SA or move the wireless transceivers serving each SA. As an example, SA coverage may increase to allow more client devices to connect to the wireless network 100 during peak periods and decrease during non-peak periods.
In wireless network 100, non-stationary device 104d (e.g. NSD1) is covered by both SAs 102c and SA 102d (SA3 and SA4) and will report its location as being either SA 102c or SA 103d (SA3 or SA4). This means that, depending on network load or signal strengths, it is possible for device 104d to change between SA 102c and SA 102d over time, which is illustrated in Table 2 below:
TABLE 2Latest 4 SA update records corresponding to NSD1SA identifierDevice identifierTimeSA3NSD12012 07 06 14:23:37SA4NSD12012 07 06 15:21:42SA4NSD12012 07 06 16:25:51SA3NSD12012 07 06 17:29:04
Because of this, it is actually not possible to assume that a change of SA identifier corresponds to a change of location by the non-stationary device 104d or implies actual physical movement of the non-stationary device 104d. In cases where the exact layout of the wireless network 100 and the coverage of its SA 102a-102d is unknown or cannot be accessed (e.g. in the case an OTT solution) it is not possible to know that a transition between two SAs represents a movement nor know anything about the likelihood of it actually representing movement.
As future wireless networks will consist of overlapping networks (e.g. WiFi, 2G, 3G, and LTE/LTE Advanced and others) and as the coverage areas of SAs of future wireless networks tend to get smaller and smaller, devices will be able to connect to more SA while remaining in the same location. This means there will be more uncertainty as to whether a SA transition represents actual movement of non-stationary devices, which makes the problem of using SA-ids as an indication of actual movement of the device more problematic. This problem is illustrated in FIG. 1c for the case of a cellular mobile network.
FIG. 1c is a schematic illustration of an example mobile network 110 in which the SAs are outdoor cells 112a-112d of the mobile network 110, some of which overlap with an indoor cell 102e (e.g. a femtocell or other indoor SA), which provides non-stationary device 104d (e.g. NSD1) with mobile network coverage within the building 120.
Considering this topology, there are:                Four cells 112a-112d (e.g. Cells 1, 2, 3, and 4) covering the area surrounding the building 120;        One indoor cell 102e (e.g. cell i) covering building 120; and        One non-stationary device 104d (e.g. NSD1) in the building 120.        
With this topology, non-stationary device 104d is attached to cell 112e (e.g. cell i) because it is within the building 120. However, non-stationary device 104d may also become attached to cells 112a or 112b (e.g. Cell 1 or Cell 2) when it is close to the windows of building 120 or any other location where the signal strength of cell 102e (e.g. cell i) is lower than the outdoor cells 102a and 102b. 
As a result, an application using mobile network location update logs to monitor the number of people carrying non-stationary devices such as non-stationary device 104d coming in and out of building 120 cannot interpret a transition from cell 112e (cell i) to cell 112a (Cell 1) or from cell 112e (Cell i) to cell 112b (Cell 2) as a non-stationary device leaving the building. On the other hand, a transition towards cells 112c and 112d (Cells 3 and 4) or any other cell that does not have coverage over the building can be safely interpreted by the application as a non-stationary device 104d leaving the building 120.
In a mobile network 110, a non-stationary device 104d-104f is very often in the coverage of more than one cell of the mobile network 110. When performing mobility analytics using mobile network cell/location update logs provided by the mobile network 110, this means that for a given subscriber, a change of cell cannot always be interpreted as a change of location. This is referred to as SA or cell swapping noise. This issue is applicable to other wireless networks that receive SA updates from devices within the network.
Therefore, there is a significant need to provide a mechanism for efficiently detecting SA swapping noise in wireless network service update logs and accurately determine when a non-stationary device 104d has changed location within a wireless network.